# LM7909L-TA3-T

**UTC(Unisonic Tech)** · Linear Voltage Regulators (LDO) · TO-220

LM7909L-TA3-T from UTC(Unisonic Tech), in a TO-220. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | GND | power_in | Common ground pin of the -9V regulator; the datasheet gives no separate electrical limit for this pin. |
| 2 | INPUT | power_in | Negative unregulated input supply, with an absolute maximum input voltage of -35V; the LM7909 output is specified with VIN from -11.5V to -23V (test condition VIN=-15V). |
| 3 | OUTPUT | power_out | Regulated -9V output (typical -9.0V at TJ=25C) that is current-limited to 1A, with a typical peak current of 2.2A. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | UTC(Unisonic Tech) |
| Package | TO-220 |
| Category | Power Management ICs |
| Pins | 3 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Output Voltage | VOUT | -8.64 | -9 | -9.36 | V | TJ=25C | 5 |
| Output Voltage | VOUT | -8.55 |  | -9.45 | V | VIN=-11.5V~-23V, IOUT=5mA~1A, PD≦15W | 5 |
| Line Regulation | VOUT |  | 10 | 180 | mV | VIN=-11.5V~-26V TJ=25C | 5 |
| Line Regulation | VOUT |  | 5 | 90 | mV | VIN=-12V~-18V TJ=25C | 5 |
| Load Regulation | VOUT |  | 12 | 180 | mV | IOUT=5mA~1A TJ=25C | 5 |
| Load Regulation | VOUT |  | 4 | 90 | mV | IOUT=250mA~750mA TJ=25C | 5 |
| Quiescent Current | IQ |  | 3 | 6 | mA | TJ=25C | 5 |
| Quiescent Current Change | IQ |  | 0.05 | 0.5 | mA | IOUT=5mA~1A | 5 |
| Quiescent Current Change | IQ |  | 0.1 | 1 | mA | VIN=-11.5V~-26V | 5 |
| Ripple Rejection | RR | 54 | 60 |  | dB | VIN=-12.5V~-22.5V, f=120Hz | 5 |
| Input Voltage | VIN |  |  | -35 | V |  | 3 |
| Output Current | IOUT |  |  | 1 | A |  | 3 |
| Operating Temperature | TOPR | -40 |  | 85 | C |  | 3 |
| Storage Temperature | TSTG | -65 |  | 150 | C |  | 3 |
| Junction to Ambient Thermal Resistance | θJA |  | 65 |  | C /W |  | 3 |
| Junction to Case Thermal Resistance | θJC |  | 5 |  | C /W |  | 3 |
| Dropout Voltage | VD |  | 2 |  | V | IOUT=1A TJ=25C | 5 |
| Output Noise Voltage | eN |  | 175 |  | μV | f=10Hz~100kHz TA=25C | 5 |
| Output Voltage Drift | VOUT/T |  | -0.6 |  | mV/C | IOUT=5mA | 5 |
| Peak Current | IPEAK |  | 2.2 |  | A | TJ=25C | 5 |

## CAD (KiCad official)

- Symbol: `LM7909L-TA3-T`
- Footprint: `Package_TO_SOT_THT:TO-220-3_Vertical`
- 3D model: TO-220 (KiCad packages3D, STEP)
- 3D model files: `lm7909l-ta3-t-etched.step` / `lm7909l-ta3-t-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lm7909l-ta3-t.step` / `lm7909l-ta3-t.glb` are the bare package body.

## Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

- **Datasheet:** [UTC(Unisonic Tech) datasheet](docs/lm7909l-ta3-t-datasheet.pdf) (8 pp, sha256 `48805386c54c2ca0`, retrieved 2026-11-05, tier: manufacturer)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/lm7909l-ta3-t-datasheet.pdf)